Mix together the almond milk and apple cider vinegar and set aside.
Place the flour, sugar and salt in a food processor and pulse to combine. Add the coconut oil and blend well until absolutely no lumps of coconut oil remain. If your food processor isn't very big you may need to do this in two batches
With the motor running, drizzle in the almond milk until the pastry starts sticking together. You may not need to add all of the milk or you may have to add a teaspoon of ice water if it isn't quite enough liquid to bring it together.
Tip the pastry out onto a floured surface and gently knead it into a ball, be careful not to overwork it. Set aside to rest while you prepare the filling.
*At this point the pastry can be refrigerated or frozen if not using straight away. Double wrap in clingfilm and then freeze. Allow to defrost overnight in the refrigerator then leave the dough at room temperature for an hour before rolling out to make it easier to work with.
Mix together the blueberries, sugar, cornflour, cinnamon and lemon juice in a large bowl. Set aside.
Divide the pastry in half and shape each half into a ball. Roll one half out on a floured surface into a large circle about 3mm/1/8in thick. Carefully lift it into a 9 inch pie dish and press into the edges, trim off the excess pastry, leaving a couple of cm overhanging.
Sprinkle over the Tbsp of semolina then tip in the blueberry filling and spread level. Set aside.
*See post above for photo instructions for making a lattice and for making pastry braids.
Pop the pie in the fridge for 20-30 minutes while you preheat the oven to 200C/400F/gas mark 6.
Brush the top of the pie with soy milk and sprinkle with granulated sugar. Bake for 20 minutes then turn the oven down to 180C/350F/gas mark 4 and bake for a further 30-40 minutes until the filling is bubbling and the crust is golden. If the crust starts to darken too much before the pie is done then loosely cover it with tin foil partway through baking.
Allow the pie to cool for at least 3 hours at room temperature before serving. Store any leftovers in the refrigerator for up to 5 days.
Pastry adapted from: https://vanillaandbean.com/how-to-make-a-coconut-oil-pie-crust/